Gas cooking burner with enhanced air entrainment and system and method incorporating same

ABSTRACT

A gas cooking system having a gas cooking burner that includes a gas line, a first gas port coupled to the gas line, and a second gas port disposed downstream from the first gas port, wherein at least one of the first and second gas ports comprises a non-circular geometry adapted to increase air entrainment, the second gas port further being non-rectangular if the first gas port has a circular geometry.

BACKGROUND

The invention relates generally to gas cooking systems and, more particularly, to gaseous fuel-air mixing techniques in a gas burner of gas cooking systems.

Conventional gas cooking systems, such as those found in households, have one or more burners in which gas is mixed with air and burned at a cooktop. To improve combustion and reduce undesirable emissions, these gas burners often mix the gas with air in a primary air entrainment region and a secondary air entrainment region. The primary air entrainment region typically comprises a gas orifice that directs a gas stream into a venturi assembly, such that air is pulled into the gas stream in the space between and surrounding the gas orifice and the venturi assembly. In addition, a fan may blow the air into the gas stream to enhance the primary air entrainment. The resulting gas-air mixture subsequently flows to a plurality of burner ports, which exhaust the gas-air mixture to the cooktop for combustion. The secondary air entrainment region resides directly downstream of these burner ports, where additional air is pulled into the exhausted gas-air mixture. Thus, the primary and second air entrainment regions supplement one another to provide the overall entrainment of air into the gas supplied to the gas burners.

Unfortunately, the existing techniques for primary and secondary air entrainment do not sufficiently entrain air into the gas stream, thereby leading to poor combustion and undesirable emissions. This limitation of existing air entrainment techniques is even more apparent for higher gas flow rates. As a result, the flames that burn the gas-air mixture from the gas ports can be characterized as relatively long flames, which may not satisfy the industry standards for fabric ignition at these higher gas flow rates. Accordingly, at the expense of heat output, existing gas cooking systems typically limit the maximum gas flow rate to meet industry standards for fabric ignition and emissions.

Accordingly, it would be desirable to develop a gas cooking system that has enhanced burner performance achieved through improved air entrainment into the gas in the gas burner, while satisfying industry standards for emissions and fabric ignition.

BRIEF DESCRIPTION

In accordance with certain embodiments, the present technique has a gas cooking system including a gas cooking burner that includes a gas line, a first gas port coupled to the gas line, and a second gas port disposed downstream from the first gas port, wherein at least one of the first and second gas ports comprises a non-circular geometry adapted to increase air entrainment, the second gas port further being non-rectangular if the first gas port has a circular geometry.

In accordance with certain embodiments, the present technique has a method of operating a gas cooking burner. The method includes receiving a gas from a gas feed line, flowing the gas out through a first gas port for primary air entrainment and passing the gas into a venturi section. The method includes exhausting the gas through a second gas port for secondary air entrainment, wherein at least one of the first and second gas ports comprises a non-circular geometry, the second gas port further being non-rectangular if the first gas port has a circular geometry.

In accordance with certain embodiments, the present technique has a method of manufacturing a gas cooking burner including, providing a venturi section, positioning a first gas port directing a gas stream into the venturi section, and disposing a second gas port downstream from the venturi section, wherein at least one of the first and second gas ports comprises a non-circular geometry, the second gas port further being non-rectangular if the first gas port has a circular geometry.

DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

FIG. 1 is a block diagram illustrating a gas burner system with a gas burner in accordance with embodiments of the present technique;

FIG. 2 is a diagrammatical representation of a circular gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 3 is a diagrammatical representation of a multiple opening gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 4 is a diagrammatical representation of a triangular gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 5 is a diagrammatical representation of a rectangular gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 6 is a diagrammatical representation of a pipe elliptical nozzle gas port a gas burner system in accordance with embodiments of the present technique;

FIG. 7 is a diagrammatical representation of a linear converging elliptical gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 8 is a diagrammatical representation of a lobed gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 9 is a diagrammatical representation of a daisy shaped gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 10 is a diagrammatical representation of a ring shaped gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 11 is a diagrammatical representation of a chevron shaped gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 12 is a diagrammatical representation of a trip wire across a gas port of a gas burner system in accordance with embodiments of the present technique;

FIG. 13 is a flow chart illustrating a process for operating a gas burner system having at least one non-circular gas port in accordance with embodiments of the present technique; and

FIG. 14 is a flow chart illustrating a process for manufacturing a gas burner system having at least one non-circular gas port and/or a gas/air temperature differential mechanism in accordance with embodiments of the present technique.

DETAILED DESCRIPTION

As discussed in detail below, embodiments of the present technique function to enhance the entrainment of air into gas in a gas burner. In the various embodiments described in detail below, gas comprises a gaseous fuel, such as natural gas, methane, propane, liquefied petroleum gas (LPG), butane, and so forth. FIG. 1 illustrates a gas cooking system 10, according to an embodiment, for use in a gas operated cooking appliance, such as, but not limited to, gas stoves, gas cookers, gas hobs, and gas ovens. In the embodiment illustrated in FIG. 1, gas cooking system 10 comprises a gas burner unit 12 that receives a supply of combustible gas from a gas line 14 via a pressure regulator 16. A conduit, such as tubing 18, then delivers the gas to a first gas port 20. The gas is then passed into a venturi section 22 and is finally exhausted via the gas burner 24 at the second gas port 26. In this embodiment, the venturi section 22 comprises a converging-diverging section. Alternatively, the venturi section 22 may comprise a converging section without the subsequent divergent section. The second gas port 26 comprises a plurality of burner ports for secondary air entrainment to generate flames for cooking at the gas burner 24. The gas burner 24 also comprises a burner cap 28 that is disposed over the gas burner 24.

In operation, the gas burner unit 12 mixes the gas with air in a primary air entrainment region 30 adjacent the first gas port 20 and in a secondary air entrainment region 32 adjacent the second gas port 26. Specifically, the primary air entrainment region 30 is located around and between the first gas port 20 and the venturi section 22. In this primary air entrainment region 30, the abrupt ejection of gas from the first gas port 20 and the venturi section 22 functions to entrain air into the gas flow, thereby providing a preliminary gas-air mixture that collectively flows toward the second gas port 26 further downstream. At the second gas port 26, the gas-air mixture exits into environmental air at the secondary air entrainment region 32, which promotes further air entrainment. In this region 32, the gas burner unit 12 also ignites the gas-air mixture to create a flame for cooking. In the illustrated embodiment, the first gas port 20 comprises a non-circular geometry to increase air entrainment at the primary air entrainment region 30, while the second gas port 26 may have a variety of circular, rectangular, or non-circular/non-rectangular geometries. In some embodiments, the second gas port 26 may comprise a non-circular/non-rectangular geometry to increase air entrainment at the secondary air entrainment region 32, while the first gas port 20 may have a variety of circular or non-circular geometries. Moreover, certain embodiments have non-circular or non-circular/non-rectangular geometries for both the first and second ports 20 and 26. As discussed in further detail below, the non-circular geometry may comprise openings that are oval, elliptical, square, rectangular, triangular, lobed (e.g., cross, daisy), ring-shaped, converging channel, diverging channel, serrated, crown, chevron, split (e.g., by trip wire), or other shapes. Moreover, the non-circular geometry may include a pattern of multiple openings. These non-circular geometries induce turbulence, which substantially increases the entrainment of air into the gas flow.

In the presently contemplated embodiment, the gas cooking system 10 comprises a gas/air temperature differential mechanism 36 that is operatively coupled to the primary air entrainment region 30. The gas/air temperature differential mechanism 36 is adapted to increase a gas/air temperature differential adjacent the first gas port 20. The increase in the gas/temperature differential is achieved by increasing a density ratio of entrained air relative to the gas by controlling a temperature of the gas and/or the ambient air.

In certain embodiments, the gas/air temperature differential mechanism 36 comprises a gas heating mechanism 38 adapted to heat gas flowing through the gas burner 24. The gas heating mechanism 38 may comprise a variety of active or passive heating mechanisms, such as heat generated by the operation of the gas cooking system 10. For example, an embodiment of the gas cooking system 10 may be configured such that the gas line 14 passes through an operationally heated region of the gas cooking system 10. In operation of this embodiment, the heat generated by the gas burner 24 at least partially transfers to the gas line 14, thereby increasing the gas/air temperature differential. Moreover, certain embodiments of the gas/air temperature differential mechanism 36 have an air cooling mechanism 40 that is adapted to decrease the temperature of air entrained at the first gas port 20. For example, the air cooling mechanism 40 may comprise a variety of active or passive cooling mechanisms, such as environmental air drawn into the primary air entrainment region 30. More specifically, embodiments of the air cooling mechanism 40 may include an environmental air channel with an inlet to environmental air remote from the gas burner 24 and having an exit adjacent the first gas port 20. As will be appreciated by those skilled in the art, a number of variations may be devised for heating and cooling mechanisms 38 and 40 for the gas cooking system 10 performing the function as described above.

By way of example, FIGS. 2-12 diagrammatically illustrate various configurations that may be implemented for the first and/or second gas ports 20 and 26 for the gas cooking system of FIG. 1. As illustrated in FIG. 2, one configuration 42 comprises a gas port 44 having a circular opening 46 that may be used at one of the first gas port 20 and the second gas port 26 in combination with at least one non-circular configurations of the first and second gas ports 20 and 26. Alternatively, other embodiments may have non-circular configurations of the first and/or second gas ports 20 and 26. For example, FIG. 3 illustrates one exemplary configuration 48 having a plurality of openings 50, which may serve as the first gas port 20 and/or the second gas port 26. Further, FIG. 4 illustrates an alternative configuration 52 having a triangular opening 54, and FIG. 5 illustrates an alternative configuration 56 having a rectangular opening 58.

FIGS. 6 and 7 diagrammatically illustrate elliptical configurations for the first gas port 20 and/or the second gas port 26. For example, FIG. 6 illustrates an elliptical nozzle 60 having a major diameter (A)62 and a minor diameter (B)64. The elliptical nozzle 60 also may span a length (L)66. Alternatively, FIG. 7 illustrates a converging elliptical nozzle 68 with a tapering section 70 having a circular section 72 at the first end 76 and having an elliptical section 74 at the second end 78. As illustrated, the circular section 72 has a diameter (D)80, which tapers over a length (L)82 to a major diameter (A)84 and a minor diameter (B)86 of the elliptical section 74. In other embodiments, the first and/or second gas ports 20 and 26 may simply have an elliptical opening, rather than a nozzle structure as illustrated in FIGS. 6 and 7.

FIG. 8 diagrammatically represents an exemplary lobed configuration 88 that may be employed in one or both of the first and second gas ports 20 and 26. The illustrated configuration 88 has a nozzle or head 90 with a lobed opening 92. As shown, the lobed opening 92 comprises a plurality of lobes 94 extending from a core 96. Specifically, the illustrated lobes 94 extend in four directions from the core 96, thereby forming a cross-shaped or X-shaped lobed opening 92. Alternatively, certain other embodiments of the lobed opening 92 may comprise different numbers and configurations of lobes. For example, the lobed opening 92 may comprise one lobe that forms a slot configuration. Further, the lobed opening 92 may comprise a cloverleaf shape or a daisy shape. FIG. 9 diagrammatically represents an exemplary configuration 98 of a lobed nozzle in a daisy shape. Specifically, the illustrated nozzle 98 has a nozzle 100 with a plurality of lobes 102 extending from a core 104 in a daisy shape.

It should be noted that a variety of other non-circular geometries may be employed for the first and/or second gas ports 20 and 26, thereby enhancing primary and secondary air entrainment. Some other examples of such non-circular ports include a ring shaped opening, a port having a trip wire or a turbulent stimulator that causes a flow of gas to become turbulent and a port having a chevron nozzle with triangular openings at periphery of the nozzle to enhance air entrainment. FIG. 10 diagrammatically illustrates an exemplary ring shaped configuration 106 for the first gas port 20 and/or the second gas port 26. The illustrated configuration 106 has a nozzle 108 with an annular ring shaped opening 110. FIG. 11 illustrates an exemplary configuration 112 with a nozzle 114 having a chevron 116 to enhance air entrainment. The illustrated configuration has a plurality of triangular protrusions 118 extending from the center 120 of the nozzle 114. FIG. 12 illustrates an exemplary configuration 122 of a nozzle 124 having a trip wire 126 attached to the gas port 128 of the nozzle 124.

FIG. 13 illustrates an exemplary process 130 for operating a gas burner system having at least one non-circular gas port in accordance with embodiments of the present technique. The process 130 begins with receiving a gas from a gas feed line (block 132). Typically, the gas feed line receives a gas flow from a supply, for example, a gas supply network, gas cylinder, gas tank, and so forth. At block 134, the process 130 proceeds by flowing the gas from the gas feed line through a first circular/non-circular gas port to achieve primary air entrainment of gas. The first gas port may comprise various non-circular geometries, such as a triangular geometry, a rectangular geometry, a ring-shaped geometry, an elliptical geometry, a lobed geometry, and so forth.

Next, at block 136, the process 130 then proceeds by passing gas flowing out of the first port into a venturi section. The process 130 then proceeds to exhaust the gas through a second circular/non-circular gas port for secondary air entrainment (block 138). Again, the geometry of this port may comprise various non-circular, non-rectangular geometries, such as a triangular geometry, a ring-shaped geometry, an elliptical geometry, a lobed geometry, and so forth. Moreover, the process 130 may combust the gas-air mixture to create flames that may be used for cooking activities by a user of the gas cooking system.

Moreover, the process 130 described above may comprise the act of increasing a gas/air temperature differential between gas and air adjacent the first gas port via a gas/air temperature differential mechanism (block 140). As will be apparent to one skilled in the art, increasing the gas/air temperature differential may comprise heating the gas. Alternatively, increasing the gas/air temperature differential may comprise cooling air entrained at the first gas port.

Referring now to FIG. 14, an exemplary process 142 for manufacturing a gas burner system having at least one non-circular gas port and/or a gas/air temperature differential mechanism in accordance with embodiments of the present technique is illustrated. The process 142 begins at block 144 by providing a venturi section in the gas burner system. The venturi section may be provided in a vertical setup. At block 146, the process 142 proceeds by positioning a first circular/non-circular gas port directing a gas stream from a gas line into the venturi section. Next, the process 142 proceeds by disposing a second circular, rectangular, or non-circular/non-rectangular gas port downstream from the venturi section (block 148).

The process 142 as described above comprises providing non-circular port geometry for at least one of the first and second gas ports to increase the primary and secondary air entrainment, respectively. The process 142 may also include positioning a gas/air temperature differential mechanism adjacent the first gas port (block 150) to increase a gas/air temperature differential adjacent the first gas port. The gas/air temperature differential mechanism may comprise a gas heating mechanism to heat gas flowing through the gas burner. Alternatively, the gas/air temperature differential mechanism may comprise an air cooling mechanism to decrease an air temperature of air entrained at the first gas port.

The various aspects of the method described hereinabove have utility in gas operated cooking appliances for example, gas cooktops, gas cookers, gas hobs, and gas ovens. As noted above, the method described here may be advantageous for such systems for enhancing primary and secondary air entrainment of gas while satisfying industry standards for emissions and fabric ignition.

While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention. 

1. A gas cooking system, comprising: a gas cooking burner, comprising: a gas line; a first gas port coupled to the gas line; and a second gas port disposed downstream from the first gas port, wherein at least one of the first and second gas ports comprises a non-circular geometry adapted to increase air entrainment, the second gas port further being non-rectangular if the first gas port has a circular geometry.
 2. The gas cooking system of claim 1, wherein the non-circular geometry comprises a lobed opening.
 3. The gas cooking system of claim 2, wherein the lobed opening comprises a cross shape.
 4. The gas cooking system of claim 2, wherein the lobed opening comprises a cloverleaf shape.
 5. The gas cooking system of claim 1, wherein the non-circular geometry comprises a plurality of grouped openings.
 6. The gas cooking system of claim 5, wherein at least one of the plurality of grouped openings has a non-circular shape.
 7. The gas cooking system of claim 1, wherein the non-circular geometry comprises a triangular opening.
 8. The gas cooking system of claim 1, wherein the non-circular geometry comprises a rectangular opening.
 9. The gas cooking system of claim 1, wherein the non-circular geometry comprises a square opening.
 10. The gas cooking system of claim 1, wherein the non-circular geometry comprises an elliptical opening.
 11. The gas cooking system of claim 1, wherein the non-circular geometry comprises a ring shaped opening.
 12. The gas cooking system of claim 1, wherein the non-circular geometry comprises an opening having a trip wire.
 13. The gas cooking system of claim 1, wherein the non-circular geometry comprises an opening having a chevron.
 14. The gas cooking system of claim 1, wherein the non-circular geometry comprises an opening having a daisy nozzle.
 15. The gas cooking system of claim 1, wherein the gas cooking burner comprises a venturi section disposed between the first and second gas ports.
 16. The gas cooking system of claim 15, wherein the venturi section comprises a converging section.
 17. The gas cooking system of claim 15, wherein the venturi section comprises a converging-diverging section.
 18. The gas cooking system of claim 1, wherein the gas cooking burner comprises a gas/air temperature differential mechanism adapted to increase a gas/air temperature differential adjacent the first gas port.
 19. The gas cooking system of claim 18, wherein the gas/air temperature differential mechanism comprises a gas heating mechanism adapted to heat gas flowing through the gas cooking burner.
 20. The system of claim 19, wherein the gas heating mechanism comprises an operationally heated region of the gas cooking system disposed adjacent the gas line, wherein the operationally heated region is adapted to heat in response to operation of the gas cooking system.
 21. The gas cooking system of claim 18, wherein the gas/air temperature differential mechanism comprises an air cooling mechanism adapted to decrease an air temperature of air entrained at the first gas port.
 22. The gas cooking system of claim 21, wherein the air cooling mechanism comprises an environmental air channel having an inlet to environmental air remote from the gas cooking burner and having an exit adjacent the first gas port.
 23. A method of operating a gas cooking burner, comprising: receiving a gas from a gas feed line; flowing the gas out through a first gas port for primary air entrainment; passing the gas into a venturi section; and exhausting the gas through a second gas port for secondary air entrainment, wherein at least one of the first and second gas ports comprises a non-circular geometry, the second gas port further being non-rectangular if the first gas port has a circular geometry.
 24. The method of claim 23, comprising increasing a gas/air temperature differential between gas and air adjacent the first gas port via a gas/air temperature differential mechanism.
 25. The method of claim 24, wherein increasing the gas/air temperature differential comprises heating the gas.
 26. The method of claim 24, wherein increasing the gas/air temperature differential comprises cooling air entrained at the first gas port.
 27. The method of claim 23, wherein passing the gas into a venturi section comprises passing the gas through a converging-diverging section.
 28. The method of claim 23, wherein passing the gas into a venturi section comprises passing the gas through a converging section.
 29. A method of manufacturing a gas cooking burner, comprising: providing a venturi section; positioning a first gas port directing a gas stream into the venturi section; and disposing a second gas port downstream from the venturi section, wherein at least one of the first and second gas ports comprises a non-circular geometry, the second gas port further being non-rectangular if the first gas port has a circular geometry.
 30. The method of claim 29, wherein positioning the first gas port comprises providing the first gas port with the non-circular geometry to increase primary air entrainment.
 31. The method of claim 29, wherein disposing the second gas port comprises providing the second gas port with a non-circular, non-rectangular geometry to increase secondary air entrainment.
 32. The method of claim 29, comprising providing a gas/air temperature differential mechanism to increase a gas/air temperature differential adjacent the first gas port.
 33. The method of claim 32, wherein providing a gas/air temperature differential mechanism comprises coupling a gas heating mechanism to heat gas flowing through the gas cooking burner.
 34. The method of claim 32, wherein providing a gas/air temperature differential mechanism comprises coupling an air cooling mechanism adapted to decrease an air temperature of air entrained at the first gas port.
 35. A gas cooking burner, comprising: means for flowing gas between a first gas port and a second gas port downstream from the first gas port; and means for non-circular exhaustion of a flow stream into air from at least one of the first and second gas ports, the second gas port being non-rectangular if the first gas port has a circular geometry.
 36. The gas cooking burner of claim 35, comprising means for increasing a gas/air temperature differential adjacent the first gas port.
 37. A gas cooking system, comprising: a gas cooking burner, comprising: a gas line; a first gas port coupled to the gas line; and a second gas port disposed downstream from the first gas port, wherein the second gas port comprises a non-circular, non-rectangular geometry adapted to increase air entrainment.
 38. The gas cooking system of claim 37, wherein the first gas port comprises a non-circular geometry.
 39. The gas cooking system of claim 38, wherein the non-circular geometry is selected from a group consisting of a lobed opening, a triangular opening, a rectangular opening, a square opening, an elliptical opening, a ring shaped opening, an opening having a trip wire, an opening having a chevron, and an opening having a daisy nozzle.
 40. The gas cooking system of claim 38, wherein the non-circular geometry comprises a plurality of grouped openings.
 41. The gas cooking system of claim 40, wherein at least one of the plurality of grouped openings has a non-circular shape.
 42. The gas cooking system of claim 37, wherein the second gas port comprises a triangular opening.
 43. The gas cooking system of claim 37, wherein the second gas port comprises a lobed opening.
 44. The gas cooking system of claim 37, wherein the second gas port comprises an elliptical opening.
 45. The gas cooking system of claim 37, wherein the second gas port comprises a ring shaped opening.
 46. The gas cooking system of claim 37, wherein the second gas port comprises an opening having a trip wire.
 47. The gas cooking system of claim 37, wherein the second gas port comprises an opening having a chevron.
 48. The gas cooking system of claim 37, wherein the second gas port comprises an opening having a daisy nozzle.
 49. The gas cooking system of claim 37, wherein the gas cooking burner comprises a venturi section disposed between the first and second gas ports. 